var code; // 在全局定义验证码
$(function () {
    var show_num = [];
    draw(show_num);
    $("#canvas").on('click', function () {
        draw(show_num);
    })

    layui.use('form', function () {
        var form = layui.form;
        form.on('submit(login)', function (setdata) {
            var val = setdata.field.vcode.toLowerCase();
            var num = show_num.join("");
            if (val == '') {
                layer.msg("请输入验证码!");
                draw(show_num);
                $("#inputvcode").val("")
            } else if (val == num) {
            return true;
               /* $.ajax({
                    url: "/login",
                    type: "get",
                    data: {
                        username: setdata.field.username
                    },
                    success: function (data) {
                    alert(data)

                        if (setdata.field.password == data.password) {
                        $.cookie("loginUserName", data.username)
                            layer.msg("登录成功");
                            window.location.href = "http://localhost:8080/"

                        } else {
                        alert(data)
                            layer.msg("用户名或密码不正确");
                            draw(show_num);
                            $("#inputvcode").val("")
                        }
                    }
                })*/
            } else {
                layer.msg("验证码错误！请重新输入!");
                draw(show_num);
                $("#inputvcode").val("")
            }
            return false;
        });
    });

    function draw(show_num) {
        var canvas_width = $('#canvas').width();
        var canvas_height = $('#canvas').height();
        var canvas = document.getElementById("canvas");//获取到canvas的对象，演员
        var context = canvas.getContext("2d");//获取到canvas画图的环境，演员表演的舞台
        canvas.width = canvas_width;
        canvas.height = canvas_height;
        var sCode = "a,b,c,d,e,f,g,h,i,j,k,m,n,p,q,r,s,t,u,v,w,x,y,z,A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";
        var aCode = sCode.split(",");
        var aLength = aCode.length;//获取到数组的长度
        for (var i = 0; i < 4; i++) { //这里的for循环可以控制验证码位数（如果想显示6位数，4改成6即可）
            var j = Math.floor(Math.random() * aLength);//获取到随机的索引值
            // var deg = Math.random() * 30 * Math.PI / 180;//产生0~30之间的随机弧度
            var deg = Math.random() - 0.5; //产生一个随机弧度
            var txt = aCode[j];//得到随机的一个内容
            show_num[i] = txt.toLowerCase();
            var x = 10 + i * 20;//文字在canvas上的x坐标
            var y = 20 + Math.random() * 8;//文字在canvas上的y坐标
            context.font = "bold 23px 微软雅黑";
            context.translate(x, y);
            context.rotate(deg);
            context.fillStyle = randomColor();
            context.fillText(txt, 0, 0);
            context.rotate(-deg);
            context.translate(-x, -y);
        }
        for (var i = 0; i <= 5; i++) { //验证码上显示线条
            context.strokeStyle = randomColor();
            context.beginPath();
            context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);
            context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);
            context.stroke();
        }
        for (var i = 0; i <= 30; i++) { //验证码上显示小点
            context.strokeStyle = randomColor();
            context.beginPath();
            var x = Math.random() * canvas_width;
            var y = Math.random() * canvas_height;
            context.moveTo(x, y);
            context.lineTo(x + 1, y + 1);
            context.stroke();
        }
    }

//得到随机的颜色值
    function randomColor() {
        var r = Math.floor(Math.random() * 256);
        var g = Math.floor(Math.random() * 256);
        var b = Math.floor(Math.random() * 256);
        return "rgb(" + r + "," + g + "," + b + ")";
    }
})



